(debug): Bind a bunch of vars, like last-command, to

neutral values.  Save the outer values in debugger-last-command, etc.
Put those saved values back into effect when returning.
(debugger-eval-expression): Put the saved values into effect
while evaluating, and store modified values back into
debugger-outer-... after evaluating.

diff --git a/lisp/emacs-lisp/debug.el b/lisp/emacs-lisp/debug.el
index 9a98e47766fa21d5b7a8212ef113aa6a2f79818b..717b1aceb83e674d816fd438aed882d27df7a454 100644 (file)
--- a/lisp/emacs-lisp/debug.el
+++ b/lisp/emacs-lisp/debug.el
@@ -30,6 +30,19 @@
 (defvar debug-function-list nil
   "List of functions currently set for debug on entry.")
 
+(defvar debugger-outer-track-mouse)
+(defvar debugger-outer-last-command)
+(defvar debugger-outer-this-command)
+(defvar debugger-outer-unread-command-char)
+(defvar debugger-outer-unread-command-events)
+(defvar debugger-outer-last-input-event)
+(defvar debugger-outer-last-command-event)
+(defvar debugger-outer-last-nonmenu-event)
+(defvar debugger-outer-last-event-frame)
+(defvar debugger-outer-standard-input)
+(defvar debugger-outer-standard-output)
+(defvar debugger-outer-cursor-in-echo-area)
+
 ;;;###autoload
 (setq debugger 'debug)
 ;;;###autoload
@@ -52,62 +65,95 @@ first will be printed into the backtrace buffer."
        (debugger-step-after-exit nil)
        ;; Don't keep reading from an executing kbd macro!
        (executing-macro nil)
-       last-command this command
-       (cursor-in-echo-area nil))
-    (unwind-protect
-       (save-excursion
-         (save-window-excursion
-           (pop-to-buffer debugger-buffer)
-           (erase-buffer)
-           (let ((standard-output (current-buffer))
-                 (print-escape-newlines t)
-                 (print-length 50))
-             (backtrace))
-           (goto-char (point-min))
-           (debugger-mode)
-           (delete-region (point)
-                          (progn
-                            (search-forward "\n  debug(")
-                            (forward-line 1)
-                            (point)))
-           (debugger-reenable)
-           (cond ((memq (car debugger-args) '(lambda debug))
-                  (insert "Entering:\n")
-                  (if (eq (car debugger-args) 'debug)
-                      (progn
-                        (backtrace-debug 4 t)
-                        (delete-char 1)
-                        (insert ?*)
-                        (beginning-of-line))))
-                 ((eq (car debugger-args) 'exit)
-                  (insert "Return value: ")
-                  (setq debugger-value (nth 1 debugger-args))
-                  (prin1 debugger-value (current-buffer))
-                  (insert ?\n)
-                  (delete-char 1)
-                  (insert ? )
-                  (beginning-of-line))
-                 ((eq (car debugger-args) 'error)
-                  (insert "Signalling: ")
-                  (prin1 (nth 1 debugger-args) (current-buffer))
-                  (insert ?\n))
-                 ((eq (car debugger-args) t)
-                  (insert "Beginning evaluation of function call form:\n"))
-                 (t
-                  (prin1 (if (eq (car debugger-args) 'nil)
-                             (cdr debugger-args) debugger-args)
-                         (current-buffer))
-                  (insert ?\n)))
-           (message "")
-           (let ((inhibit-trace t)
-                 (standard-output nil)
-                 (buffer-read-only t))
+       ;; Save the outer values of these vars for the `e' command
+       ;; before we replace the values.
+       (debugger-outer-track-mouse track-mouse)
+       (debugger-outer-last-command last-command)
+       (debugger-outer-this-command this-command)
+       (debugger-outer-unread-command-char unread-command-char)
+       (debugger-outer-unread-command-events unread-command-events)
+       (debugger-outer-last-input-event last-input-event)
+       (debugger-outer-last-command-event last-command-event)
+       (debugger-outer-last-nonmenu-event last-nonmenu-event)
+       (debugger-outer-last-event-frame last-event-frame)
+       (debugger-outer-standard-input standard-input)
+       (debugger-outer-standard-output standard-output)
+       (debugger-outer-cursor-in-echo-area cursor-in-echo-area))
+    ;; Don't let these magic variables affect the debugger itself.
+    (let ((last-command nil) this-command track-mouse
+         unread-command-char unread-command-events
+         last-input-event last-command-event last-nonmenu-event
+         last-event-frame
+         (standard-input t) (standard-output t)
+         (cursor-in-echo-area nil))
+      (unwind-protect
+         (save-excursion
+           (save-window-excursion
+             (pop-to-buffer debugger-buffer)
+             (erase-buffer)
+             (let ((standard-output (current-buffer))
+                   (print-escape-newlines t)
+                   (print-length 50))
+               (backtrace))
+             (goto-char (point-min))
+             (debugger-mode)
+             (delete-region (point)
+                            (progn
+                              (search-forward "\n  debug(")
+                              (forward-line 1)
+                              (point)))
+             (debugger-reenable)
+             (cond ((memq (car debugger-args) '(lambda debug))
+                    (insert "Entering:\n")
+                    (if (eq (car debugger-args) 'debug)
+                        (progn
+                          (backtrace-debug 4 t)
+                          (delete-char 1)
+                          (insert ?*)
+                          (beginning-of-line))))
+                   ((eq (car debugger-args) 'exit)
+                    (insert "Return value: ")
+                    (setq debugger-value (nth 1 debugger-args))
+                    (prin1 debugger-value (current-buffer))
+                    (insert ?\n)
+                    (delete-char 1)
+                    (insert ? )
+                    (beginning-of-line))
+                   ((eq (car debugger-args) 'error)
+                    (insert "Signalling: ")
+                    (prin1 (nth 1 debugger-args) (current-buffer))
+                    (insert ?\n))
+                   ((eq (car debugger-args) t)
+                    (insert "Beginning evaluation of function call form:\n"))
+                   (t
+                    (prin1 (if (eq (car debugger-args) 'nil)
+                               (cdr debugger-args) debugger-args)
+                           (current-buffer))
+                    (insert ?\n)))
              (message "")
-             (recursive-edit))))
-      ;; So that users do not try to execute debugger commands
-      ;;  in an invalid context
-      (kill-buffer debugger-buffer)
-      (store-match-data debugger-match-data))
+             (let ((inhibit-trace t)
+                   (standard-output nil)
+                   (buffer-read-only t))
+               (message "")
+               (recursive-edit))))
+       ;; So that users do not try to execute debugger commands
+       ;;  in an invalid context
+       (kill-buffer debugger-buffer)
+       (store-match-data debugger-match-data)))
+    ;; Put into effect the modified values of these variables
+    ;; in case the user set them with the `e' command.
+    (setq track-mouse debugger-outer-track-mouse)
+    (setq last-command debugger-outer-last-command)
+    (setq this-command debugger-outer-this-command)
+    (setq unread-command-char debugger-outer-unread-command-char)
+    (setq unread-command-events debugger-outer-unread-command-events)
+    (setq last-input-event debugger-outer-last-input-event)
+    (setq last-command-event debugger-outer-last-command-event)
+    (setq last-nonmenu-event debugger-outer-last-nonmenu-event)
+    (setq last-event-frame debugger-outer-last-event-frame)
+    (setq standard-input debugger-outer-standard-input)
+    (setq standard-output debugger-outer-standard-output)
+    (setq cursor-in-echo-area debugger-outer-cursor-in-echo-area))
     (setq debug-on-next-call debugger-step-after-exit)
     debugger-value))
 \f
@@ -226,7 +272,31 @@ Applies to the frame whose line point is on in the backtrace."
        ;; old buffer deleted
        (setq debugger-old-buffer (current-buffer)))
     (set-buffer debugger-old-buffer)
-    (eval-expression exp)))
+    (let ((track-mouse debugger-outer-track-mouse)
+         (last-command debugger-outer-last-command)
+         (this-command debugger-outer-this-command)
+         (unread-command-char debugger-outer-unread-command-char)
+         (unread-command-events debugger-outer-unread-command-events)
+         (last-input-event debugger-outer-last-input-event)
+         (last-command-event debugger-outer-last-command-event)
+         (last-nonmenu-event debugger-outer-last-nonmenu-event)
+         (last-event-frame debugger-outer-last-event-frame)
+         (standard-input debugger-outer-standard-input)
+         (standard-output debugger-outer-standard-output)
+         (cursor-in-echo-area debugger-outer-cursor-in-echo-area))
+      (prog1 (eval-expression exp)
+       (setq debugger-outer-track-mouse track-mouse)
+       (setq debugger-outer-last-command last-command)
+       (setq debugger-outer-this-command this-command)
+       (setq debugger-outer-unread-command-char unread-command-char)
+       (setq debugger-outer-unread-command-events unread-command-events)
+       (setq debugger-outer-last-input-event last-input-event)
+       (setq debugger-outer-last-command-event last-command-event)
+       (setq debugger-outer-last-nonmenu-event last-nonmenu-event)
+       (setq debugger-outer-last-event-frame last-event-frame)
+       (setq debugger-outer-standard-input standard-input)
+       (setq debugger-outer-standard-output standard-output)
+       (setq debugger-outer-cursor-in-echo-area cursor-in-echo-area)))))
 \f
 (defvar debugger-mode-map nil)
 (if debugger-mode-map